diff --git a/README.rst b/README.rst
index d0613137dca8dbd6fefacd97d55e711084e9ff44..7bcc202a84a1212fd7eea1303202e3101d63f0be 100644
--- a/README.rst
+++ b/README.rst
@@ -33,6 +33,7 @@ Python versions:
 - *Python 3.10*
 - *Python 3.11*
 - *Python 3.12*
+- *Python 3.13*
 
 
 Why was this tool created?
diff --git a/docs/releasenotes.rst b/docs/releasenotes.rst
index 6384623418746955979ccc5e37fe561491361be9..30bfeba410d7d82eabbf863e20ac572c9dd01b2f 100644
--- a/docs/releasenotes.rst
+++ b/docs/releasenotes.rst
@@ -29,6 +29,7 @@ Resolved issues:
 
   - `GC-50: Drop support for Python 3.8 <https://projects.majic.rs/gimmecert/issues/GC-50>`_
   - `GC-48: Update all requirements <https://projects.majic.rs/gimmecert/issues/GC-48>`_
+  - `GC-47: Support for Python 3.13 <https://projects.majic.rs/gimmecert/issues/GC-47>`_
 
 
 1.0.0
diff --git a/functional_tests/test_csr.py b/functional_tests/test_csr.py
index 18368f32f025034d6c5c0d9380fffc5e94e0b77d..cb7f78da8b4b01f0f9cd2b12aacc8cf4f1ab7a2c 100644
--- a/functional_tests/test_csr.py
+++ b/functional_tests/test_csr.py
@@ -37,22 +37,22 @@ def test_commands_report_csr_option_as_available():
     stdout, stderr, exit_code = run_command("gimmecert", "server", "-h")
 
     # John notcies the option for passing-in a CSR.
-    assert " --csr " in stdout
-    assert " -c " in stdout
+    assert " --csr" in stdout
+    assert " -c" in stdout
 
     # He checks help for the client command.
     stdout, stderr, exit_code = run_command("gimmecert", "client", "-h")
 
     # John notcies the option for passing-in a CSR.
-    assert " --csr " in stdout
-    assert " -c " in stdout
+    assert " --csr" in stdout
+    assert " -c" in stdout
 
     # He checks help for the renew command.
     stdout, stderr, exit_code = run_command("gimmecert", "renew", "-h")
 
     # John notcies the option for passing-in a CSR.
-    assert " --csr " in stdout
-    assert " -c " in stdout
+    assert " --csr" in stdout
+    assert " -c" in stdout
 
 
 def test_client_certificate_issuance_by_passing_csr_as_file_rsa(tmpdir):
diff --git a/functional_tests/test_renew.py b/functional_tests/test_renew.py
index 925d22e0a5763f3fc975e1c8580f8eff0cdd59f4..c446cf3b1643ed283cc23e9fcfbb6c59e8c9a6f9 100644
--- a/functional_tests/test_renew.py
+++ b/functional_tests/test_renew.py
@@ -317,8 +317,8 @@ def test_renew_update_dns_option(tmpdir):
 
     # He notices there is an option for updating DNS subject
     # alternative names.
-    assert " --update-dns-names DNS_NAMES" in stdout
-    assert " -u DNS_NAMES\n" in stdout
+    assert " --update-dns-names" in stdout
+    assert " -u" in stdout
 
     # Based on help description, this seems to be exactly what he
     # needs.He goes ahead and runs the renewal command, specifying
diff --git a/provision.sh b/provision.sh
index 68c0fa937b1548a3e2fb802fa43a30e648ab8015..9745b6e4bd035a2c0a8440d36894bac1def5952c 100755
--- a/provision.sh
+++ b/provision.sh
@@ -44,7 +44,7 @@ apt-get install -qq -y make build-essential libssl-dev zlib1g-dev libbz2-dev lib
 sudo -i -u vagrant gpg -q --import /vagrant/provision/python_releases_signing_keys.pub
 
 # Download and build additional Python versions.
-python_versions=("3.9.18" "3.10.13" "3.11.8" "3.12.2")
+python_versions=("3.9.18" "3.10.13" "3.11.8" "3.12.2" "3.13.7")
 work_directory="/home/vagrant/src"
 
 echo "Setting-up work directory."
diff --git a/setup.py b/setup.py
index 816fa8e2064eb4e94a5c1021110c5fe0683c65bc..57e3e9153a966e59d62611fec1439455c7712624 100755
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@ from setuptools import setup, find_packages
 
 README = open(os.path.join(os.path.dirname(__file__), 'README.rst')).read()
 
-python_requirements = ">=3.9,<3.13"
+python_requirements = ">=3.9,<3.14"
 
 install_requirements = [
     'cryptography>=45.0,<45.1',
@@ -92,6 +92,7 @@ setup(
         'Programming Language :: Python :: 3.10',
         'Programming Language :: Python :: 3.11',
         'Programming Language :: Python :: 3.12',
+        'Programming Language :: Python :: 3.13',
         'Topic :: Internet :: WWW/HTTP',
         'Topic :: Internet :: WWW/HTTP :: Site Management',
         'Topic :: Security',
diff --git a/tox.ini b/tox.ini
index 6f1e8ef07d97760c532eed274dc29caec404825d..bd3b5be32403bed6e32be7ca90969b925fc021d3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -31,6 +31,7 @@ basepython =
   py310: python3.10
   py311: python3.11
   py312: python3.12
+  py313: python3.13
 
 deps =
   .[test]